Many methods of providing alarms responsive to human senses are known such as audible, visual, and tactile.
As a safety measure it may be required to alert persons in a tower, for example a tower used for production of energy from wind, of the motion of an internal access elevator where a hazard may result. This is particularly important where such an elevator is not necessarily provided with a protective hoistway to prevent body parts from invading the volume corresponding to the path of the elevator throughout its range of motion, such as would be the case of elevators for public use. Such tower elevators are commonly used to transport technicians and their tools from the lower platform to the nacelle at the top of the tower, and to the intervening spaces. Additionally, such an elevator may be required to descend while unpowered, for example during a power failure. Where a power supply is not available, standard powered alarms such as a strobe light, may or may not be powered such as during a power failure.
The elevator as disclosed herein differs from an elevator used to transport the general public within a building in that it is typically but not necessarily a simpler construction and may be guided with cables tensioned between the top and base of the tower rather than using rails attached to the tower structure. Additionally, the hoist is typically mounted within the car rather than at the top of the structure.